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Coherent CW

ARRL Technical Information Service page · TIS Menu page

Coherent CW was invented by Raymond C. Petit, W7GHM, to significantly reduce the power required for communication by using precise timing to reduce the necessary bandwidth to send a morse code signal--just 9Hz for 12 wpm CW.  To prove the point, Andy McCaskey, WA7ZVC, assembled his station using a Ten Tec PM-2 QRP transceiver. 

 

Articles

 

Note: Some of the following articles are in Adobe Portable Document Format (PDF) files. To view and print these files, you'll need a copy of Adobe's Acrobat Reader program. (Version 7.0 or later required). More information here.

 

  • Coherent CW (891,844 bytes, PDF file)
    QST September 1975, pp. 26-27
    Amateur radio's new state of the art?
  • Coherent CW -- The Concept -- Part 1 (369,331 bytes, PDF file)
    QST May 1981, pp. 11-14
    Would you think that you could decrease your transmitter output power by a factor of 10 and increase signal readability by the same amount -- simultaneously? It's being done now.
  • Coherent CW -- The Practical Aspects -- Part 2 (404,922 bytes, PDF file)
    QST June 1981, pp. 18-23
    You'll now see how you can put the concept into practice.
  • A DSP Version of Coherent-CW (CCW) (652,378 bytes, PDF file)
    QEX February 1994, pp. 25-30
    Obtain the advantages of coherent detection of Morse signals using DSP.

    Note:

    Contact information for suppliers mentioned in the above articles should first be confirmed using TIS Address Database Search.

    Bibliography (Members Only)

    ARRL Periodicals Index Search - This database contains the QST index from 1915 to the present and the QEX index from 1981 to the present. For QST issues from 1970 to the present, and some selected articles back to 1922 (when construction articles featuring tubes began in earnest), identifying keywords have been added to the technical articles. By entering keywords (ANTENNA) or combinations of keywords (CONSTRUCTION ANTENNA VERTICAL HF) into the Title words: field, you may create dynamic bibliographies.
    Technical article KEYWORD list. Hints for more successful searching

    Suggested keywords for more articles like the ones on this page are COHERENT CW

    Web Links:

     

  • Coherent CW: Some Theory
    CCW is not magic, it is just the application of well-known pieces of communication theory
  • Coherent CW
    . . . a mode whose time has come?
  • CCW Notes
    These notes have been prepared by Peter Lumb G3IRM to give you some idea how coherent c.w. operates.
  • Coherent CW ...
    "The More You Know About a Signal, the Easier it is to Copy"
  • Latest COHERENT Uses Lattice Coding

     

    Article Reprints:

     

    You can get a photocopy of any ARRL published article for $3 ($5 for nonmembers) for each article requested. Contact the ARRL Technical Department (reprints@arrl.org ),  or 1-860-594-0390, Noon to 5PM, Tuesday through Friday, if you wish to get photocopies.

     

    This information was prepared as a membership service by the American Radio Relay League, Inc., Technical Information Service, 225 Main St., Newington, CT 06111 (860) 594-0214. Email: tis@arrl.org (Internet). ARRL HQ is glad to provide this information on the Web free of charge as a service to League members and affiliated clubs.

    If you have any questions concerning the reproduction or distribution of this material, please contact:

     


    • Page last modified: 02:36 PM, 25 Sep 2007 ET
    Page author: tis@arrl.org
    Copyright © 2007, American Radio Relay League, Inc. All Rights Reserved.